This invention relates to a multiprocessor system which is capable of processing information at a high speed.
Since a super computer system has been manufactured by Cray Research Inc., Minn., U.S.A. and sold in the name of Cray-1 from 1978. Strong demand has occurred for the ability to carry out a scientific calculation at a high speed.
Under the circumstances, a recent requirement is directed to a computer system which can process not only a great number of vector elements at a high speed but also a great deal of jobs.
In order to satisfy such a requirement, a proposal has been offered about a computer system which comprises a plurality of vector calculation units specific to a vector calculation and an instruction control unit for controlling the vector calculation units. The computer system can certainly execute the vector calculation at a high speed by using the plurality of the vector calculation units and is very effective in processing a great deal of the vector elements at a high speed. However, the computer system mentioned above is not always suitable for processing a great deal of jobs because such jobs are not restricted to the vector calculation alone and any other processing can not be executed during the vector calculation.
On the other hand, a wide variety of computer systems have been proposed each of which comprises a plurality of processors and which may be collectively called multiprocessor systems. Such multiprocessor systems can quickly process a great deal of jobs and can therefore improve throughput. Herein, it is usual that each processor in such a multiprocessor system is similar in structure and operation to one another and comprises a single vector calculation unit in addition to a processing unit for a scalar calculation and an address calculation. This shows that each processor itself can not process a great number of vector elements at a high speed and consequently inevitably takes a long time for the vector calculation. Therefore, each processor is not suitable for carrying out the vector calculation of a great number of vector elements. This means that the conventional multiprocessor systems can not flexibly assign the jobs to the plurality of the processors.
At any rate, none of conventional systems as mentioned above completely satisfy the recent requirement because both a great number of vector elements and a great deal of jobs can not be flexibly processed in the conventional systems.